Melania Trump, 47, gave a short speech at the Flag Hall and revealed she only gave the dress designer Herve Pierre two weeks to make the “gorgeous couture piece” as it had slipped her mind.
The dress was an off-shoulder number, cream in colour, and featured ruffle detailing from the top to the very bottom.
A thigh-high split in the skirt and a thin red ribbon round the waist helped Melania dazzle on stage at the ball.
For the event yesterday, the First Lady stepped out in a brocade print empire neckline dress in metallic white.
When she arrived to the event she had thrown a pale pink coat over her shoulders and she completed the look with a pair of bright pink pointed-toe stilettos.
Melania’s hair was worn in tousled waves and she wore heavy eye make-up, plenty of bronzer and a pink lip.
Alongside her short speech, Melania posed next to the dress and also with designer Herve.
Last Friday, Melania stepped out with her husband US President Donald Trump, 72, before he made his Iran deal speech.
She wore a beige trench coat with black buttons and a snack print trim.
Melania appeared to channel business as she stood by President Donald Trump’s side.
Underneath her smart coat, the First Lady wore black cigarette cut trousers, flat shoes with a pointed toe and dark sunglasses sat on her nose.
The pair were photographed as Donald Trump spoke to the press before boarding Marine One for Beltsville, Maryland, in Washington, DC.
The pair looked serious as President Trump prepared for a highly-anticipated address in which be would refuse to certify the 2015 Iranian nuclear deal.
He warned that the US may walk away from the deal – which he called “one of the worst” agreements in history.
Melania’s coat appeared to be from high-end designer Burberry, a company which is is famous for its trench coats.
The British brand specialising the outerwear prices jackets at between £1200 and £1500.